1. Field of the Invention
The invention relates to a door lock assembly, and particularly, to an improvement of a lock assembly to control a door latch.
2. Description of the Related Art
A typical lock assembly is shown in FIGS. 1 to 3 and comprises a housing 1000 to be mounted on the outer side of a door, a lever 2001 operable from the outside of a door, a lever operated linkage mechanism provided inside an inner casing 2000, an inner knob 4000 associated with an inner cap 3000 and a latch 5000 to be operated by the linkage mechanism. The lock assembly additionally comprises a key operated lock 2003 above the lever 2001 to control a deadbolt (not shown). When the lever 2001 is pressed, it actuates the components of the linkage mechanism in a manner shown by FIGS. 2 and 3 (please see arrows) so that a transmission rod 2002 moves a cam wheel 5001 which in turn retracts the latch 5000. The inner cap 3000 houses a mechanism cooperable with the inner knob 4000 to actuate a cam wheel 5002 and to thereby retract the latch 5000.
In the aforementioned lock assembly, the mechanism that actuates the latch 5000 from the outside of the door is independent from that which actuates the latch 5000 from the inside of the door. Therefore, a latch of the type having two cam wheels 5002 and 5001 must be used for connection with two independent actuation mechanisms. Various forms of latches are in existence. It is desirable to provide a lock assembly of the above-mentioned type that accommodates a latch which has only one cam wheel or two cam wheels.